Search results for " rando"
showing 10 items of 498 documents
Update I. A systematic review on the efficacy and safety of chloroquine/hydroxychloroquine for COVID-19
2020
Purpose To assess efficacy and safety of chloroquine (CQ)/hydroxychloroquine (HCQ) for treatment or prophylaxis of COVID-19 in adult humans. Materials and methods MEDLINE, PubMed, EMBASE and two pre-print repositories (bioRxiv, medRxiv) were searched from inception to 8th June 2020 for RCTs and nonrandomized studies (retrospective and prospective, including single-arm, studies) addressing the use of CQ/HCQ in any dose or combination for COVID-19. Results Thirty-two studies were included (6 RCTs, 26 nonrandomized, 29,192 participants). Two RCTs had high risk, two ‘some concerns’ and two low risk of bias (Rob2). Among nonrandomized studies with comparators, nine had high risk and five moderat…
Training programme for novice physical activity instructors using Teaching Personal and Social Responsibility (TPSR) model : a programme development …
2021
Previous research indicates that programmes employing Hellison?s Teaching Personal and Social Responsibility (TPSR) model in physical activity have had a positive impact on youth development by increasing participants? positive values, autonomy, life skills, and prosocial behaviour. Despite encouraging results of the effects of TPSR-based programmes, there remains lack of research on the effective content of these programmes, and their implementation and evaluation. The current protocol article describes the development of a TPSR-based instructor training programme and a plan for an intervention study in which novice instructors learn to understand and apply the TPSR model in practice. The …
Associations between parental rules, style of communication and children's screen time
2015
Background Research suggests an inverse association between parental rules and screen time in pre-adolescents, and that parents’ style of communication with their children is related to the children’s time spent watching TV. The aims of this study were to examine associations of parental rules and parental style of communication with children’s screen time and perceived excessive screen time in five European countries. Methods UP4FUN was a multi-centre, cluster randomised controlled trial with pre- and post-test measurements in each of five countries; Belgium, Germany, Greece, Hungary and Norway. Questionnaires were completed by the children at school and the parent questionnaire was brough…
Soft errors in commercial off-the-shelf static random access memories
2016
International audience; This article reviews state-of-the-art techniques for the evaluation of the effect of radiation on static random access memory (SRAM). We detailed irradiation test techniques and results from irradiation experiments with several types of particles. Two commercial SRAMs, in 90 and 65 nm technology nodes, were considered as case studies. Besides the basic static and dynamic test modes, advanced stimuli for the irradiation tests were introduced, as well as statistical post-processing techniques allowing for deeper analysis of the correlations between bit-flip cross-sections and design/architectural characteristics of the memory device. Further insight is provided on the …
Fast equivariant JADE
2013
Independent component analysis (ICA) is a widely used signal processing tool having applications in various fields of science. In this paper we focus on affine equivariant ICA methods. Two such well-established estimation methods, FOBI and JADE, diagonalize certain fourth order cumulant matrices to extract the independent components. FOBI uses one cumulant matrix only, and is therefore computationally very fast. However, it is not able to separate identically distributed components which is a major drawback. JADE overcomes this restriction. Unfortunately, JADE uses a huge number of cumulant matrices and is computationally very heavy in high-dimensional cases. In this paper, we hybridize the…
On the Statistical Properties of Phase Crossings and Random FM Noise in Double Rayleigh Fading Channels
2016
In this paper, we study the statistics of phase processes and random frequency modulation (FM) noise encountered in double Rayleigh fading channels. The Rayleigh processes making up the double Rayleigh channel are assumed to be independent but not necessarily identically distributed. The Doppler power spectral densities of these processes are supposed to be symmetric about the carrier frequency. Under these fading conditions, we derive first an expression for the joint probability density function (jpdf) of the phase process and its rate of change. Capitalizing on this jpdf formula, we then investigate the probability density function (pdf) and cumulative distribution function (cdf) of rand…
Tests for time reversibility: a complementarity analysis
2003
Abstract Since time reversibility (TR) is a necessary condition for an independent and identically distributed (iid) sequence, several tests for TR have been suggested to be applied as tests for model misspecification. In this paper, we analyze possible complementarities among two well known TR tests (Ramsey and Rothman's test, and Chen et al.'s test) in two situations: (1) the fitted model is a linear ARMA model when the true data generating process is a nonlinear-in-mean model (either threshold autoregressive or bilinear), and (2) the fitted model is a symmetric GARCH model but the true process belongs to the asymmetric GARCH family (either EGARCH or GJR). The results suggest that there a…
Statistical Properties of Double Hoyt Fading With Applications to the Performance Analysis of Wireless Communication Systems
2018
In this paper, we investigate the statistical properties of double Hoyt fading channels, where the overall received signal is determined by the product of two statistically independent but not necessarily identically distributed single Hoyt processes. Finite-range integral expressions are first derived for the probability density function (PDF), cumulative distribution function (CDF), level-crossing rate (LCR), and average duration of fades of the envelope fading process. A closed-form approximate solution is also deduced for the LCR by making use of the Laplace approximation theorem. Applying the derived PDF of the double Hoyt channel, we then provide analytical expressions for the average…
Modelling the occurrence of rainy days under a typical Mediterranean climate
2014
The statistical inference of the alternation of wet and dry periods in daily rainfall records can be achieved through the modelling of inter-arrival time-series, IT, defined as the succession of times elapsed from a rainy day and the one immediately preceding it. In this paper, under the hypothesis that ITs are independent and identically distributed random variables, a modelling framework based on a generalisation of the commonly adopted Bernoulli process is introduced. Within this framework, the capability of three discrete distributions, belonging to the Hurwitz–Lerch-Zeta family, to reproduce the main statistical features of IT time-series was tested. These distributions namely Lerch-se…
Horizontal visibility graphs: exact results for random time series
2009
The visibility algorithm has been recently introduced as a mapping between time series and complex networks. This procedure allows us to apply methods of complex network theory for characterizing time series. In this work we present the horizontal visibility algorithm, a geometrically simpler and analytically solvable version of our former algorithm, focusing on the mapping of random series (series of independent identically distributed random variables). After presenting some properties of the algorithm, we present exact results on the topological properties of graphs associated with random series, namely, the degree distribution, the clustering coefficient, and the mean path length. We sh…